Esters of silicic acid.



-more fully the following example UNITED STATES PATENT orricn ,LUDWIG "KNORR, or V JENA, AVND HEBMANN WEYLAND, or BERLIN, GERMANY, ASSIGNORS ro SYNTHETIC PATENTS 00. me, or NEW YORK, .11. 1,1 conrom:

TION OF NEW YORK.

No Drawing.

To all whom, it may concern: a 7

Be it known that we, LUDWIG KNOBR, doctor of philosophy, professor of chemistry, and HERMANN WEYLANn, doctor of philosophy, citizens of the German Empire,

residing, respectively, at Jena, Grand Duchy of Saxe-Weimar, and Berlin, Klngdom of Prussia, Germany, have invented new and useful Improvements in Esters of Silicic Acid, of which the following is .a specification. p

\Ve have found that new esters of the orthosilicic acid can beobtained'by heating the known silicic esters e. g. the tetraethyl silicic ester Si(OG H with polyvalent alcohols. According to the quantities of the polyvalent alcohols used different esters can.

thus be obtained. From glycol e. g. the two esters having most probably the following formulas can be obtained:

OCHz-CHaOH Bic-o CHu-CHz-OH I ocmonaon s1 oomcriaon ML \Q Y From glycerin The new esters have proved to be therapeutically valuable as remedies against tuberculosis, the daily dose being from 2- to 3 grams. The esters in which all OH groups of the alcohols are linked together with the silicic acid are insoluble in water; those still containing free hydroxy groups are soluble in water. I

In order to illustrate the new process is 'ven:-4 molecules of glycerin (previously reed from water by heating it to 200 C.) and '1 molecule of tetraethyl silicic ester (boiling point 166 C.) are located together in an autoclave (whlle the mixture is being Specification of Letters Patent.

nsrnns or srmcrc ACID.

stirred) to 150 c. A limpid liquidresults fromwhich the ethylalcohol split offduring formula I It is soluble inwater, alcohol and glycerin insoluble in ether, ligroin and chloroform;

In an analogous way other'of'the above mentioned esters can be obtained e. g. the glycermorthosilicate Having most secondary probably the formula:

' rig-con 'crnon H o o-- a v S1 o m m To'- produoe this ester 2 molecules of glycerin and 1 molecule'of silicic acid Patented Apr. 11, 1916.

.Application filed Deeember29,1914. Serial at. 879,528. I A

ethylester are heated as described above. 7

After distilling oflfthe alcohol a solid, brittle mass is obtained which can be easily ground into a fine powder. As far as solubility and saponification are concerned, the-- secondary glycerin orthosilicateresembles the-primary ester.

The tertiary glycerinorthosilicate having I most probably the formula; 1

is prepared as follows :4=' molecules of. glycerin and 3 molecules of silicic ester are mixed, thus forming an emulsion; If this emulsion is heated--for several'h'ours in an via being therapeutically valuable products,

substantially as described.

2. The new prlmary estersof orthosilicic acid with polyvalent alcohols, which are generally gelatin like products soluble in alcohol, and

being therapeutically valuable products, substantially as described.

3. The'new esters of orthosilicic acid with 'glycerin, which are generally gelatin like products soluble in alcohol, and being ther'a peutically valuable products, substantially as described.

4. The new primary glycerin ester of orthosilicic acid, having most probably the structure graphically represented:

- OCH2-CHOH.CH2OH oom.osou.cmon

oomcnoaomon OCHZ-CHOH-CHBOH I Which is a gelatin like product soluble in water and alcohol, and which is a therapeutically valuable product substantially as described.

In testimony whereof we have hereunto set our hands in the presence of two subscribing witnesses.

PROF. DR. LUDWIG KNORR. DR. HERMANN WEYLAND.

Witnesses as to L. K.: v

FREDERICK J; SCHUSSEL, VICTOR GUGGENBERGER,

' Witnesses as to Hermann Weyland:

HENRY HASPER,

WOLDEMAR HAUPT. 

